Malicious PDF — malware analysis report

Static analysis result for SHA-256 279a78ea3f6bdec8…

MALICIOUS

PDF

77.0 KB Created: 2021-05-11 19:29:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ddafa31879a8147f337b67d879ee710f SHA-1: d216044c11dc4999d3a8696f48f4d342f96ed1c5 SHA-256: 279a78ea3f6bdec813c8ff0e11c9f7175745c982d72d2d2e869b043719a2df2a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many pointing to seemingly benign documents, but also includes a link to a suspicious domain 'resalured.ru'. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external links, suggesting a link farm or redirection mechanism. ClamAV detection as 'Pdf.Phishing.Trojan' and the ML classifier's high score confirm malicious intent, likely related to phishing or malware delivery via the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://resalured.ru/strik?utm_term=what+are+the+three+categories+of+cpt+codes+quizlet
    • https://cdn.sqhk.co/jorawuge/gfOhihb/bba_aviation_plc_annual_report_2018.pdf
    • https://cdn.sqhk.co/zudipoje/jdigP67/891840985.pdf
    • https://cdn.sqhk.co/xonivozew/ggjbujf/fukutoxesuwaxalodew.pdf
    • https://cdn.sqhk.co/gaxudofexal/ktiiHX3/63844074317.pdf
    • https://finibolamojirum.weebly.com/uploads/1/3/5/3/135341575/jizuvorotupira.pdf
    • https://cdn.sqhk.co/zezinojox/bQs7hb1/kolup.pdf
    • https://cdn.sqhk.co/benibavagoge/jahhRgf/90s_music_radio_2020.pdf
    • https://cdn.sqhk.co/tasokuxu/aZgeWia/wuduzegitew.pdf
    • https://wemavepudobug.weebly.com/uploads/1/3/4/1/134108610/naniwubilu-jedoja-vetisudosol-lotika.pdf
    • https://daxivikulogator.weebly.com/uploads/1/3/4/3/134308382/f1fef5e7.pdf
    • https://cdn.sqhk.co/ridefapagol/igjkZhj/global_outbreak_doomsday_edition_free_download.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c305ab47-cb07-4832-ad9a-2fdfaef79826/xutofesinoputovitakananun.pdf
    • https://s3.amazonaws.com/vososasoxumete/68783828341.pdf
    • https://s3.amazonaws.com/dowadotiju/refazutogof.pdf
    • https://s3.amazonaws.com/fizaxo/mixed_addition_and_subtraction_worksheets_grade_2.pdf
    • https://s3.amazonaws.com/pululusodogi/fugonun.pdf
    • https://s3.amazonaws.com/jidagafinuxesu/imagenes_de_caras_de_emociones_para_imprimir.pdf
    • https://uploads.strikinglycdn.com/files/f04107fa-88bb-4769-8f88-66f3282c09c0/do_you_need_simple_syrup_for_mojitos.pdf
    • https://s3.amazonaws.com/xijilesuzuxo/3rd_grade_spelling_words_wonders.pdf
    • https://uploads.strikinglycdn.com/files/4b3eefdf-8d1f-49d2-b7bb-0c775ca18757/will_the_lamborghini_gallardo_go_up_in_value.pdf
    • https://uploads.strikinglycdn.com/files/e59822db-1c40-40af-a543-7010edea4e0e/84048756174.pdf
    • https://s3.amazonaws.com/libeganot/54894374990.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eef8.bin
ac6983384aa4844b33bffebb9b5e6fa872665c37ac4138fa041ce89d41c18e74
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF8 5608 bytes
font_01_sfnt_off00010215.bin
63e71c8d9261e9a23a69a104672f5d1e76a6877f82b63faa1c4bddfd557d2f29
pdf-font-stream PDF embedded font (sfnt) at offset 0x10215 10544 bytes